Can the Valar Sentence People to Death?

[Galadriel]

Originally Posted by Eomer of the Rohirrim

I don't remember anything in the text about this matter, but I'm sure they would not make such a decision without consulting Eru.

That's what I thought.

Let's assume a scenario. Suppose Maglor just randomly turns up at Alqualondë (suspension of disbelief needed at this point) and starts shooting people. Will the Valar simply banish him again, or have him killed? You can assume he lost his mind, if you like